Gross Unrealized Losses on Investment Securities and Corresponding Fair Values by Investment Category and Length of Time that Securities have been in Continuous Unrealized Loss Position (Detail) (USD $)	Sep. 30, 2014	Mar. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months Gross unrealized losses	$ 679,742	$ 2,707,418
Less than 12 months Fair value	33,313,908	65,613,686
12 months or longer Gross unrealized losses	2,468,550	399,531
12 months or longer Fair value	53,137,803	10,065,115
Total Gross unrealized losses	3,148,292	3,106,949
Total Fair value	86,451,711	75,678,801
U.S. treasuries and government agencies
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months Gross unrealized losses	7,656	995,320
Less than 12 months Fair value	1,916,094	17,004,680
12 months or longer Gross unrealized losses	764,931	151,563
12 months or longer Fair value	16,235,069	2,848,437
Total Gross unrealized losses	772,587	1,146,883
Total Fair value	18,151,163	19,853,117
Mortgage-backed
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months Gross unrealized losses	672,086	1,712,098
Less than 12 months Fair value	31,397,814	48,609,006
12 months or longer Gross unrealized losses	1,703,619	247,968
12 months or longer Fair value	36,902,734	7,216,678
Total Gross unrealized losses	2,375,705	1,960,066
Total Fair value	$ 68,300,548	$ 55,825,684